3D LOCALIZATION OF SURFACE 10-20 EEG ELECTRODES ON HIGH-RESOLUTION ANATOMICAL MR-IMAGES

A method to visualize surface EEG electrodes on conventional high-reso lution magnetic resonance (MR) images is presented. Because convention al silver or gold electrodes generate an insignificant artifactual sig nal signature in MR images, a plastic capsule filled with gadolinium-d oped water was designed to mold onto each electrode, thereby outlining the electrode surfaces as a negative imprint on MR images. MR images of the head with capsules affixed clearly demonstrated the location an d shape of the electrodes. Selected cranial tissues were identified by using semi-automatic image segmentation to determine their three-dime nsional spatial relationship to the electrodes. Such representations c ould be used as a starting point for more precise EEG source localizat ion modeling applicable to individual patients. (C) 1997 Elsevier Scie nce Ireland Ltd.